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Pinpoint Test A : U0121: Notes

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostic Overview 

Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Service Information .

Refer to Starting System for schematic and connector information.

DTC Fault Trigger Condition- 

U0121 Lost Communication With Anti-Lock Brake System (ABS) Control Module The PCM sets this DTC if data messages received from the ABS module over the High Speed Controller Area Network (HS-CAN) are missing.

Normal Operation and Fault Conditions 

REFER to Module Communications Network .

Possible Sources 

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